package org.apache.lucene.analysis;

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

import java.io.IOException;
import java.io.Reader;

/**
 * "Tokenizes" the entire stream as a single token. This is useful
 * for data like zip codes, ids, and some product names.
 */
public class KeywordAnalyzer extends Analyzer {
  public KeywordAnalyzer() {
    setOverridesTokenStreamMethod(KeywordAnalyzer.class);
  }
  @Override
  public TokenStream tokenStream(String fieldName,
                                 final Reader reader) {
    return new KeywordTokenizer(reader);
  }
  @Override
  public TokenStream reusableTokenStream(String fieldName,
                                         final Reader reader) throws IOException {
    if (overridesTokenStreamMethod) {
      // LUCENE-1678: force fallback to tokenStream() if we
      // have been subclassed and that subclass overrides
      // tokenStream but not reusableTokenStream
      return tokenStream(fieldName, reader);
    }
    Tokenizer tokenizer = (Tokenizer) getPreviousTokenStream();
    if (tokenizer == null) {
      tokenizer = new KeywordTokenizer(reader);
      setPreviousTokenStream(tokenizer);
    } else
      tokenizer.reset(reader);
    return tokenizer;
  }
}
